Patents by Inventor Didier Angebaud

Didier Angebaud has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5218637
    Abstract: According to the invention, the chip card issues a first certificate comprising its letter of credentials (Crc), an exponential (X), an optional message (M), these quantities being signed. The security module verifies the signature and in return issues a second certificate containing its letter of credentials (Crm), an exponential (Y), an optional message (M'), a cryptogram (C), these quantities being signed. A common secret key is constituted between the card and the security module by the exponentials and allows the card to interpret the cryptogram addressed to it and to act in accordance therewith.
    Type: Grant
    Filed: June 11, 1991
    Date of Patent: June 8, 1993
    Assignee: L'Etat Francais represente par le Ministre des Postes, des Telecommunications et de l'Espace
    Inventors: Didier Angebaud, Jean-Luc Giachetti, Louis Guillou, Jean-Jacques Quisquater
  • Patent number: 5218559
    Abstract: The generator of the invention includes an initialization circuit (CI) delivering four initialization words (QI, RI, SI, TI), one calculation circuit (CC) composed of four sub-units (SQ, SR, SS, ST) corresponding to four generating polynomials of orders 5, 5, 7 and 7, and finally one output logic circuit (CS) delivering a pseudo-random byte sequence.Application for systems with access control, especially television systems.
    Type: Grant
    Filed: January 8, 1992
    Date of Patent: June 8, 1993
    Assignees: France Telecom Etablissement Autonome de Droit Public (Centre National d'Etudes des Telecommunications), Etablissement Publics Telediffusion de France
    Inventors: Didier Angebaud, Jean Giachetti, Vincent Lenoir